• The Plant Pathology Journal
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• v.33 no.6
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• pp.554-560
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• 2017

After 20 years of steady increase, kiwifruit industry faced a severe arrest due to the pandemic spread of the bacterial canker, caused by Pseudomonas syringae pv. actinidiae (Psa). The bacterium penetrates the host plant primarily via natural openings or wounds, and its spread is mainly mediated by atmospheric events and cultural activities. Since the role of sucking insects as vectors of bacterial pathogens is widely documented, we investigated the ability of Metcalfa pruinosa Say (1830), one of the most common kiwifruit pests, to transmit Psa to healthy plants in laboratory conditions. Psa could be isolated both from insects feeding over experimentally inoculated plants, and from insects captured in Psa-infected orchards. Furthermore, insects were able to transmit Psa from experimentally inoculated plants to healthy ones. In conclusion, the control of M. pruinosa is recommended in the framework of protection strategies against Psa.

• Korean Journal of Veterinary Service
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• v.39 no.1
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• pp.29-34
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• 2016

This study was carried out to investigate the tick-borne pathogens from one hundred nineteen cattle farms (38 farms of Andong, 41 of Yeongju, 12 of Uiseong, 5 of Cheongsong, 5 of Yoengyang, 18 of Bonghwa) in northern areas of Gyeongbuk province by polymerase chain reaction (PCR). Among 119 cattle farms, the positive ratios against Babesia, Theileria, Anaplasma, Ehrlichia and Rickettsia were 3.4% (4/119), 10.1% (12/119), 6.7% (8/119), 1.7% (2/119) and 16.8% (20/119), respectively. Also, the PCR results revealed that 8 farms were positive for T. sergenti in positive of Theileria and 2 farms were positive for A. phagocytophilum in positive of Anaplasma. Therefore, further studies regarding vectors, environmental condition, interaction between domestic and wild animals and development of control program are needed to reduce the numbers of bovine tick-borne disease in northern areas of Gyeongbuk province.

• Korean journal of applied entomology
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• v.10 no.2
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• pp.85-89
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• 1971

An investigation was carried out to know the host range of the rice stripe virus as a basis of the disease control. 1. In order to investigate the host range of the rice stripe virus 30 species including gramineaceae and forage crop and weeds were inoculated with viruliferous Laodelphax sriatellus Fallen. As a result, 21 out of 30 species showed typical symptoms. 2. Cyperus amuricus Maximowicz var. laxus., Pycreus sanguinolentus Nees. and Eriocaulon robustius Makino, not belonging to gramineaceae were known to be new host plants of rice stripe virus. The highest infection occurred on Pycreus sanguinolentus grown widly in the wet paddy fold. 3. The number of vectors inoculated on the plants was decreased after 48 hours than that of 24 hours.

• Research in Plant Disease
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• v.20 no.3
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• pp.173-181
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• 2014

The early and accurate detection of plant viruses is an essential component to control those. Because the globalization of trade by free trade agreement (FTA) and the rapid climate change promote the country-to-country transfer of viruses and their hosts and vectors, diagnosis of viral diseases is getting more important. Because symptoms of viral diseases are not distinct with great variety and are confused with those of abiotic stresses, symptomatic diagnosis may not be appropriate. From the last three decades, enzyme-linked immunosorbent assays (ELISAs), developed based on serological principle, have been widely used. However, ELISAs to detect plant viruses decrease due to some limitations such as availability of antibody for target virus, cost to produce antibody, requirement of large volume of sample, and time to complete ELISAs. Many advanced techniques allow overcoming demerits of ELISAs. Since the polymerase chain reaction (PCR) developed as a technique to amplify target DNA, PCR evolved to many variants with greater sensitivity than ELISAs. Many systems of plant virus detection are reviewed here, which includes immunological-based detection system, PCR techniques, and hybridization-based methods such as microarray. Some of techniques have been used in practical, while some are still under developing to get the level of confidence for actual use.

• Journal of Biosystems Engineering
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• v.42 no.3
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• pp.217-226
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• 2017

Purpose: Aedes aegypti and Aedes albopictus are notorious disease vectors that spread various viruses including dengue, yellow fever, chikungunya, and Zika. Recent Zika virus outbreaks were carried by Ae. aegypti, raising awareness about the perils of its global distribution. Because Ae. albopictus is spread throughout South Korea and can carry the same viruses as Ae. aegypti, monitoring potential distributions of Ae. albopictus and Ae. aegypti is necessary. Methods: In this study, the potential distributions of Ae. albopictus and Ae. aegypti in South Korea were modeled using CLIMEX software, and changes in response to climate change were predicted. Results: The results indicated that the climatic suitability for Ae. albopictus was consistently high, while occurrence of Ae. aegypti was only predicted for Jeju Island in 2080. Conclusions: The results provide basic information for preventing the invasion of Ae. aegypti, and consequent interactions between Ae. aegypti and Ae. albopictus, which may cause severe outbreaks of dangerous diseases.

• Journal of Biomedical Engineering Research
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• v.26 no.3
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• pp.129-132
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• 2005

It is one of the most important issues to determine a target brain image that gives a common coordinate system for a constructing population-based brain atlas. The purpose of this study is to provide a simple and reliable procedure that determines the target brain image among the group based on the inherent structural information of three-dimensional magnetic resonance (MR) images. It uses only 11 lines defined automatically as a feature vector representing structural variations based on the Talairach coordinate system. Average characteristic vector of the group and the difference vectors of each one from the average vector were obtained. Finally, the individual data that had the minimum difference vector was determined as the target. We determined the target brain image by both our algorithm and conventional visual inspection for 20 healthy young volunteers. Eighteen fiducial points were marked independently for each data to evaluate the similarity. Target brain image obtained by our algorithm showed the best result, and the visual inspection determined the second one. We concluded that our method could be used to determine an appropriate target brain image in constructing brain atlases such as disease-specific ones.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.596-616
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• 2021

A global increase in fish consumption has led to a rapid expansion of aquaculture production, which has been linked to enhancing the spread of infectious diseases. Viral diseases can cause high mortality in many cultured fish species, posing a serious threat to the aquaculture industry. Infectious hematopoietic necrosis virus (IHNV) is one of the primary threats to aquacultured salmonid species, causing huge economic losses. Since the first report in cultured sockeye salmon Oncorhynchus nerka during the 1950s in North America, IHNV has spread to other regions, including Europe, Asia, South America, and Africa by transportation of infected fish and eggs, causing disease and increasing mortality in a wide variety of salmonid species. Here, we review existing information relevant to IHNV: its phylogenetic characteristics, origin, infection history, virulence determinants, susceptible hosts, vectors, and vaccine development. This review also addresses a possible cross-species transmission of IHNV to a new host, olive flounder Paralichthys olivaceus, a cultured fish of economic importance in East Asian countries.

• Research in Plant Disease
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• v.24 no.1
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• pp.9-25
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• 2018

Plant viruses cause significant yield losses and continuously threaten crop production, representing a serious threat to global food security. Studies on plant-virus interactions have contributed to increase our knowledge on plant immunity mechanism, providing new strategies for crop improvement. The prophylactic managements consist mainly following international legislations, eradication of infected plants, and application of pesticide to decrease the population of vectors. Hence, putting together the pieces of knowledge related to molecular plant immunity to viruses is critical for the control of virus disease in fields. Over the last several decades, the outstanding outcomes of extensive research have been achieved on comprehension of plant immunity to viruses. Although most dominant R genes have been used as natural resistance genes, recessive resistance genes have been deployed in several crops as another efficient strategy to control viruses. In addition, RNA interference also regulates plant immunity and contribute a very efficient antiviral system at the nucleic acid level. This review aims at describing virus disease on crops and summarizes current resistance mechanisms. Furthermore, we will discuss the current biotechnological approaches to control viral diseases and the future questions that are to be addressed to secure crop production against viruses.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.177-183
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• 2018

This study examined the seasonal, regional distribution of mosquito vectors related with disease vectors in the Jeju. From March to November, sample were collected from 11 points in four environmentally different sites in Jeju Island. Samples were collected twice a month using a black-light trap and a BG sentinel trap. Overall, five genera and seven species types of 6,042 female mosquitos were collected. Among the collected mosquitos, 4,159 (68.8%) and 1,348 (24.4%) were Culex pipiens and Aedes albopictus, respectively, making them the dominant species. Additionally, collection using the black light trap produced 72.8 entities per trap in Jungang-dong service center in the center of the city, which was the highest value, while the lowest amount of 1.4 per trap was recovered from the airport. When the BG sentinel trap was used, the largest recovery was observed in the port, where there were 71.7 entities per trap, while the lowest amount of 28.3 entities per trap was recovered at Gealmae Eco Park. The overall number of mosquitoes collected started to increase from May, and reached the largest value of 1,156 (19.1%) in August. Trapped mosquitoes are created 364 pools of up to 50 grains per pool, by season, by environmental, and by species. When the pools were used, no flaviviral infection was observed upon real time RT-PCR.

• Journal of the Korean Geographical Society
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• v.47 no.5
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• pp.677-699
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• 2012

Climate changes may cause substantial changes in spatial patterns and distribution of vector-borne diseases (VBD's), which will result in a significant threat to humans and emerge as an important public health problem that the international society needs to solve. As global warming becomes widespread and the Korean peninsula characterizes subtropical climate, the potentials of climate-driven disease outbreaks and spread rapidly increase with changes in land use, population distributions, and ecological environments. Vector-borne diseases are typically infected by insects such as mosquitoes and ticks, and infected hosts and vectors increased dramatically as the habitat ranges of the VBD agents have been expanded for the past 20 years. Medical geography integrates and processes a wide range of public health data and indicators at both local and regional levels, and ultimately helps researchers identify spatiotemporal mechanism of the diseases determining interactions and relationships between spatial and non-spatial data. Spatial epidemiology is a new and emerging area of medical geography integrating geospatial sciences, environmental sciences, and epidemiology to further uncover human health-environment relationships. An introduction of GIS-based disease monitoring system to the public health surveillance system is among the important future research agenda that medical geography can significantly contribute to. Particularly, real-time monitoring methods, early-warning systems, and spatial forecasting of VBD factors will be key research fields to understand the dynamics of VBD's.